shindo vs. atma-sphere

Neil - have you rolled any tubes yet? The chinese tubes that come stock tend to be quiet and pretty reliable (though not super long lived) but their top end is, uh, well let's say less than sweet. MP-1 and MP-3 are gorgeous sounding preamps.

what's the difference between the mp-1 and mp-3? also, what is the impact of the v-cap and caddock resistor upgrades?

Hi Tim,

My (deceased) friend,Michael, had already purchased and installed some fairly 'tasty' NOS tubes which he'd purchased from Andy at Vintage Tube Services. Some better than others; all overpriced IMO.

Anyway, the MP-3 linestage takes a pair of 12AU7's And a pair of 6SN7's; and Micheal had/has some dandies. Sylvania and RCA (red base!) 6SN7's, and a range of 12AU7's: Telefunken, Phillips, Raytheon (windmill getter!), Tung Sol blackplates, etc. I guess I like the RCA 6SN7's and the Telefunken 12AU7's best so far; but they all sound great.

The phonostage takes 3 pairs (gainstages) of 12AT7's plus one more 12AT7 which is a 'constant current' modulator (not in the signal path). I have become addicted to the GEC A2900, or its military version CV6091 (same tube.) I use them everywhere I need a 12AT7: 7 in the MP-3, 2 in my headphone amp, and four in my MC275 (McIntosh) amp. They now cost (minimum) $125 each! They have great sonics, but more important, they have the highest transconductance (a measure of a tube's gain, or 'strength') of any 12AT7. As such, they provide the best signal to noise ratio in situations like the 3 gainstages in the MP-3 phonostage -- which is what makes it actually possible to use the MP-3 with a .6mv MC cartridge and without any SUT! In my power amplifier, the 12AT7's are drivers for the KT88's, and if you use any of the four strongest KT88's as I do (EAT, GEC, Psvane, Shuguang) then this is the only driver strong enough to accurately control the grid voltage in those ultra-high-power tubes and get the best (cleanest) bass out of them. (Those four tubes all have transconductance values of 12,000 micromnhos. Every other KT88 out there is 7500 or less - usually 4500 -5500 ;~)
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For the differences between the MP-3 and MP-1 preamps, the best place to start is the Atma-Sphere website, as well as discussions and reviews.

I can tell you though that the MP-3 is not a 'baby' MP-1. They both use balanced differential circuits but different tubes. And the MP-1 is a two chassis unit (with a separate power supply.) It's also about 3x or 4x the price of the MP-3 ;~)

Capacitor upgrades are generally a good idea. Whether V-Caps are the preferred upgrade, I don't know. Capacitors are like tubes - they are to taste ;~) Ralph thinks Chris Van Hul's V-caps are special; a lot of other people like other caps better . . .

Caddock resistors can provide a warmer, smoother sound, but to hear any difference, you have to change ALL OF THEM!
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Thanks everyone for your responses. They have all been a big help.

Odds are I would get the MP3, not just for cost but also for space considerations. But the Shindo sounds awfully good too.